Warning devices for motor vehicles are useful in many situations. When an automobile is disabled due to an accident or automobile failure, it may constitute a traffic hazard to approaching vehicles, and it is desirable to warn approaching motorists of the disability. Also, assistance is frequently not readily available in such situations due to the remoteness of the location in which the disability occurs or the reluctance of passing motorists to stop and render assistance. In certain instances, an occupant of a disabled or stopped vehicle may require immediate medical attention; and, especially in such circumstances, it is crucial that passing motorists be alerted of the emergency in order to obtain prompt assistance.
One prior warning device, disclosed in U.S. Pat. No. 3,810,092, comprises a pair of rigid panels which are adapted to be removably mounted to the roof of a vehicle by suction cup feet. A plurality of message cards are supported between the panels, each bearing a different word. The cards are selectively slidable from their normal hidden position between the panels to an exposed, extended position to permit a message carried by one or a combination of the cards to be seen by oncoming motorists. One or more signal lights may also be mounted to the panels to further alert oncoming motorists.
The device shown in U.S. Pat. No. 3,810,092 would appear to have only limited visibility, particularly at night or during adverse weather conditions. The device also appears rather bulky and difficult to handle and store.
U.S. Pat. No. 2,843,952 discloses a warning device which is built into a motor vehicle. Such a device would appear to be prohibitively expensive and highly complex. Yet other prior vehicle warning systems are described in U.S. Pat. Nos. 3,668,797; 3,497,980; 3,772,811; and 4,070,775.
An effective warning device for motor vehicles must be capable of displaying a message that is highly visible and legible to approaching motorists, even at night or during adverse weather conditions when visibility is limited. A suitable device should also be portable so that it can easily be set-up for use by a single person, and compact so that it can conveniently be stored in a vehicle. A bulky warning device which is impractical to use or store within the vehicle will most likely be left at home, thereby rendering the warning device useless.